<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="./bootstrap-3.4.1-dist/css/bootstrap.min.css">
</head>

<body>
  <div class="dropdown">
    <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown"
      aria-haspopup="true" aria-expanded="true">
      Dropdown
      <span class="caret"></span>
    </button>
    <ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
      <li><a href="#">Action</a></li>
      <li><a href="#">Another action</a></li>
      <li><a href="#">Something else here</a></li>
      <li role="separator" class="divider"></li>
      <li><a href="#">Separated link</a></li>
    </ul>
  </div>

  <ol class="breadcrumb">
    <li><a href="#">Home</a></li>
    <li><a href="#">Library</a></li>
    <li class="active">Data</li>
  </ol>
</body>

</html>